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991.
NUMERICALMODELFORDYNAMICSIMULATIONOFTRAFFICFLOWWuZheng;ZengLi-nong(DepartmentAppliedMechanics,FudanUniversity,Shaghai200433,P... 相似文献
992.
993.
Yuansheng Jiang Yihan Shao Edward C. Kirby 《Fullerenes, Nanotubes and Carbon Nanostructures》1994,2(4):481-497
An algorithm to generate the molecular graphs of the trivalent clusters is presented. All the polyhedral trivalent cages with 4-16 vertices are enumerated, with particular attention being given to their symmetry, spectra and stability. The relative stability of isomers is not decided solely by their symmetry. A new kind of spectral phenomenon is reported. This is the occurrence of graphs having the same HOMO-LUMO gap, the same E and the same even-order moments. We refer to it as 'pseudo-isospectrality'. 相似文献
994.
Thomas L. Landers Melinda K. Beavers Malik Sadiq Don E. Stuart 《Computers & Industrial Engineering》1994,27(1-4):245-248
This paper describes an approach, conceptual framework, and software architecture for dynamic reconfiguration of the order picking system. The research and development project was sponsored by the Material Handling Research Center (MHRC), a National Science Foundation sponsored Cooperative Industry/University Research Center. The storage configuration is assumed to be an in-the-aisle order picking system in which stockkeeping units (SKUs) can occupy variable capacity storage locations and stock-splitting is allowed among zones (clusters). The product mix may include multiple product families with different life cycles, correlated demand within families and commonality of demand across families. 相似文献
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Methods are analyzed for increasing the propulsive thrust-efficiency characteristics of the internal duct of a gasdynamic
model with combustion by means of boosting the operational process stage. At a Mach number 5 and a stagnation temperature
between 1200 and 1500 K and 35–40 MPa stagnation pressures we investigated the effect of the degree of combustor expansion
Fc on the propulsive thrust-efficiency characteristics of a small model operating on hydrogen fuel with an air excess coefficient
of 1. The calculated predictions of the increase in the model characteristics on account of a reduced Fc were confirmed experimentally. When the combustor operates in a regine, where the heat is being supplied to a subsonic flow,
it is possible on priciple to reduce Fc to a minimum determined by the flow gas thermodynamics in the combustor.
Institute of Theoretical and Applied Mechanics of the Siberian Division of the Russian Academy of Science, 630090 Novosibirsk.
Translated from Fizika Goreniya i Vzryva,31, No. 6, pp. 49–63. 相似文献
999.
Wu Ting M. Badaye T. Morishita N. Koshizuka S. Tanaka 《Journal of Superconductivity》1996,9(6):637-645
Recently, superconducting Nd1Ba2Cu3Oy (Ndl23) thin films with high superconducting transition temperature (T
c) have been successfully fabricated at our institute employing the standard laser ablation method. In this paper, we report the results of surface characterization of the Nd123 thin films using an ultrahigh vacuum scanning tunneling microscope/spectroscopy (UHV-STM/STS) and an atomic force microscope (AFM) system operated in air. Clear spiral pattern is observed on the surfaces of Nd123 thin films by STM and AFM, suggesting that films are formed by two-dimensional island growth mode. Contour plots of the spirals show that the step heights of the spirals are not always the integer or half-integer number of thec-axis parameter of the structure. This implies that the surface natural termination layer of the films may not be unique. This result is supported byI-V STS measurements. The surface morphology of the Nd123 thin films is compared with that of thec-axis-oriented Y1Ba2Cu3Sy thin films. Surface atomic images of the as-prepared Nd123 thin films are obtained employing both STM and AFM. STS measurements show that most of the surfaces are semiconductive. The results of STS measurements together with the fact that we are able to see the surface atomic images using scanning probe microscopes suggest that exposure to air does not cause serious degradation to the as-prepared surfaces of Nd123 thin films. 相似文献
1000.